GOALI: Manufacturing Large, Diamond Single Crystals via High-Pressure, High-Temperature Growth

这一学术与工业联系机会(GOALI)奖支持与钻石单晶制造相关的新知识的研究，促进科学和促进国家繁荣、健康和安全。长期以来，钻石单晶一直被视为宝石，但由于其独特的性质，也显示出在新技术应用方面的巨大前景。虽然天然钻石是由超过100英里深处的地壳中的碳形成的，但这些条件可以在实验室中模拟，从而使用高压高温生长过程制造最高质量的人造钻石晶体。这笔赠款支持基础研究，以改进这一过程，以便能够以更大的尺寸、超高质量和更低的成本制造单晶钻石，从而使其能够应用于大功率X射线系统的光学元件，以及核反应堆和医疗应用中的辐射探测器设备、电力电子和量子计算。这项研究的结果将对经济竞争力和国家安全产生积极影响。这项研究涉及多个学科，包括先进制造、计算建模、晶体生长和材料科学。这种多学科的方法有助于扩大参与，并对工程教育产生积极影响。用来生长大型单晶的制造工艺必须达到原子级的结构完美，同时保持足够高的产量，以满足成本目标。该项目致力于在高压、高温系统中通过晶体生长来生产单晶钻石。该系统有能力生长出结晶质量最高的钻石。然而，极端压力(5 Gpa)和温度(1,500 K)使生长的直接、现场诊断和建模成为工艺改进的重要工具。该项目开发和应用基于热力学、动力学和输运的新型计算模型，以更好地了解高压高温系统中单晶金刚石生长的基本机制。这些模型通过Goali Partner，Euclid BeamLabs，LLC进行的生长实验得到验证，并应用于改善制造结果，如更大的晶体尺寸和更快的生长速度。一个重要的目标是避免工艺条件导致夹杂物，夹杂物是含有金属溶剂的微米级缺陷，在生长过程中被捕获。多尺度模型描述了原子高度的台阶，这些台阶穿过不断增长的钻石的小面移动，并预测当一系列等距离的台阶不稳定形成束状时，触发包裹体的形成。因此，通过了解集群的开始，可以通过建模和使用实验来评估创新的增长策略，例如系统的随时间变化的倾斜。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This Grant Opportunities for Academic Liaison with Industry (GOALI) award supports research that contributes new knowledge related to diamond single crystal manufacturing, promoting science and advancing national prosperity, health, and security. Diamond single crystals have long been prized as gemstones but have also shown great promise for new technical applications because of their unique properties. While natural diamonds are formed from carbon in the earth’s crust at depths greater than 100 miles, these conditions can be mimicked in the laboratory allowing synthetic diamond crystals of the highest quality to be manufactured using the High-Pressure, High-Temperature growth process. This grant supports fundamental research to improve this process so that single-crystal diamonds can be manufactured in larger sizes, at ultra-high quality, and for less cost, thus enabling application in optical elements for high-power X-ray systems, as well as in devices for radiation detectors in nuclear reactors and medical applications, power electronics, and quantum computing. Results from this research will favorably impact economic competitiveness, and national security. This research involves several disciplines including advanced manufacturing, computational modeling, crystal growth, and materials science. The multi-disciplinary approach helps broaden participation and positively impacts engineering education.Manufacturing processes employed to grow large, single crystals must achieve atomic-level structural perfection while simultaneously maintaining yields that are high enough to meet cost objectives. This project addresses the production of single-crystal diamond via crystal growth in a High-Pressure, High-Temperature system. This system has the capability to grow diamonds of the highest crystalline quality. However, extreme pressure (5 GPa) and temperature (1,500 K) make direct, in situ diagnostics of growth impossible and modeling a vital tool for process improvement. This project develops and applies novel computational models based on thermodynamics, kinetics, and transport to better understand the fundamental mechanisms responsible for single-crystal diamond growth in the High-Pressure, High-Temperature system. These models are validated via growth experiments conducted by GOALI partner, Euclid Beamlabs, LLC, and applied to improve manufacturing outcomes, such as large crystal size and increased growth rate. An important goal is to avoid process conditions leading to inclusions, which are micron-sized defects containing metallic solvent trapped during growth. Multi-scale models describe steps of atomic height that move across the facets of the growing diamond and predict when an equidistant train of steps destabilizes to form bunches, triggering inclusion formation. Understanding the onset of bunching thus allows innovative growth strategies, such as time-dependent tilting of the system, to be assessed by modeling and tested using experiments.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.